A Train Traveling at 90 Km/h Is Blowing Its Whistle

Multiple Choice

A train traveling at 90 km/h is blowing its whistle at 440 Hz as it crosses a level crossing.You are waiting at the crossing and hear the pitch of the whistle change as the train passes you.The sound you hear changes from a frequency of _____ to a frequency of _____.(Take the speed of sound to be 340 m/s.)

A) 475 Hz; 410 Hz
B) 410 Hz; 475 Hz
C) 408 Hz; 472 Hz
D) 472 Hz; 408 Hz
E) 598 Hz; 348 Hz